Change the Default Line Width for Ink Annotations

To change the default line width for ink annotations, use annotation presets. Here’s example code:

const myAnnotationPresets = instance.annotationPresets;
myAnnotationPresets["ink"] = {
  lineWidth: 3
};
instance.setAnnotationPresets(myAnnotationPresets);

Or, if you want to preserve the other values for the ink annotation, use the following code:

myAnnotationPresets['ink'] = Object.assign({}, instance.annotationPresets.ink, {
  lineWidth: 3
}

After this is run, if the user clicks the ink tool button, the line width will be set to 3, the new default, until the value is changed.